ABSTRACT Lauren K. Whiteside M.D. is a fellowship-trained, practicing emergency medicine physician with a long term career goal to become an independent, federally funded investigator capable of developing and implementing innovative systems of care from the Emergency Department (ED) for patients with prescription opioid misuse (POM) and related substance abuse, mental health and medical comorbidities. Patients with POM have high rates of comorbidity, and this K23 proposal will inform, refine and pilot a collaborative care model built from the chronic disease management framework to decrease rates of POM while addressing health services needs and comorbidity. Patients with substance use problems utilize the ED for care more than patients without these needs and thus, the ED is a critical and innovative location to initiate a collaborative care model for these patients. To reach this long-term goal, D. Whiteside has assembled a group of multidisciplinary mentors and contributors and put together a structured, tailored educational plan to learn specific skills to transition to the next stage ofher career. The short term training goals for this K23 Mentored Patient-Oriented Career Development Award are to 1) inform a collaborative care model for POM by getting formal training in health systems and mixed methods research; 2) Acquire the skills necessary to implement a collaborative care system in the ED by understanding patterns of POM and associated substance use problems, medical/psychiatric comorbidity and health service utilization; 3) Learn how to conduct randomized clinical trials and understand how to apply innovative adaptive design and pragmatic trial considerations to this highly variable population. Given the known medical, psychiatric and substance use comorbidities associated with patients with POM, a health care system approach is required to address the complexity associated with this problem. Therefore specific research aims of this proposal are to: 1) Inform content for a collaborative care model (RxCC) to decrease POM and related comorbidity by conducting semi- structured interviews with the target patient population and their care providers; 2: Refine RxCC by enrolling participants and conducting semi-structured interviews at one month to explore barriers and facilitators of healthcare utilization within the framework of collaborative care; and 3) Pilot a randomized control trial of RxCC delivered over six months compared to usual care using adaptive randomization procedures for patients in the ED with POM for feasibility and acceptability. The RCT will not be adequately powered to detect significant treatment effects, thus exploratory analyses will compare differences in health care utilization at six months as well as prescription opioid misuse (POM). This K23 Mentored Patient-Oriented Career Development Award proposal directly addresses NIDA's strategic plan outlined in 2010 by addressing treatment for POM and associated comorbidities and provides an innovative health systems approach for this complex problem.